A Pt-Au alloy catalyst of varying compositions is prepared by codeposition of Pt and Au nanoparticles onto a carbon support to evaluate its electrocatalytic activity toward an oxygen reduction reaction (ORR) with methanol tolerance in direct methanol fuel cells. The optimum atomic weight ratio of Pt to Au in the carbonsupported Pt-Au alloy (Pt-Au/C) as established by cell polarization, linear-sweep voltammetry (LSV), and cyclic voltammetry (CV) studies is determined to be 2:1. A direct methanol fuel cell (DMFC) comprising a carbon-supported Pt-Au (2:1) alloy as the cathode catalyst delivers a peak power density of 120 mW/cm 2 at 70 °C in contrast to the peak power density value of 80 mW/cm 2 delivered by the DMFC with carbonsupported Pt catalyst operating under identical conditions. Density functional theory (DFT) calculations on a small model cluster reflect electron transfer from Pt to Au within the alloy to be responsible for the synergistic promotion of the oxygen-reduction reaction on a Pt-Au electrode.

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The reactions of X3-chlorocyclotriphosphazane [EtNPCl]3 with phenols or trifluoroethanol yield the respective aryloxy-or trifluoroethoxy-containing X3-cyclotriphosphazanes [EtNP(OR)]3 (R = Cet^BM (2), CeHj (3), CeH3-ß2-3,5 (4), 6 (5), CH2CF3 (6)) as their cis-trans isomeric mixtures. The products have been characterized by IR and NMR spectroscopy. The crystal structures of both the cis (2a) and trans (2b) isomers of the p-bromophenoxy derivative have been determined by X-ray diffraction. Crystal data for 2a: triclinic, PI, a = 9.872(4) Á, b -13.438